On this, a day for the history books. The stock market on a rocket ride, blasting through a ceiling and closing at an all-time high. And, this was the scene on the floor of the new york stock exchange. Big smiles. Compare that to the dark days of the recession, this trader in despair, head in hands. So, how can we trust the stock market bounce this time? And will it bring more american jobs? Abc's linzie janis, who has covered financial markets for years, tells us. Reporter: Cheers of joy and relief from the trading floor. Is this good times ahead? Well, right now, it is a time to celebrate. Reporter: A long way from that previous high back in october 2007. The recession began just two months later. Now wall street is booming again. I love the buzz this has created. This is telling the main street investor something I've been trying to explain for over a year, that the stock market is a place you need to have your money. RepIG WINNERS? America's largest companies, now sitting on a collective cash pile of more than a trillion dollars. Those wall street titans, seeing the biggest bonuses in years. The modern american family 401 k nest egg bigger than before. From $67,000 in 2007 to $46,000 at the depth of the market in 2009. And now, higher than ever. 77,300 and climbing. When it comes to jobs, many americans are getting left behind. There are 2.2% fewer jobs today than back in 2007. 12.3 million americans are still out of work. So, if american businesses are flourishing, why aren't they hiring? We called the leaders of some of america's most profitable companies and asked them why they aren't spending their cash hiring even more workers. Hello, this is linzie janis from abc news. Those that got back to us stressed they were hiring. Still, experts tell us companies are working leaner. Outsourcing jobs with countries with cheap labor and using technology to replace factory workers. Increasingly, manufacturing is going to be a matter of computer programming, software and robots. Reporter: That's why experts say math and science degrees are golden these days. And that stock is only going up. Diane, the people we spoke to today say they've learned to All the traders we spoke to mentioned three things they are watching. The chinese economy, the european recession and, most of all, that grid lock in washington. All right, lynn see, thank you so much.

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